Return to Answer

I'm not sure where you are looking, but first look here: https://www.reddit.com/r/askscience/comments/23a96x/could_an_earth_sized_object_orbit_jupiter/

The answer is Yes; any two objects can orbit each other, include Earth and Jupiter.

You need to be concerned about the Roche Limit, which tells you how far apart they must be in order to do so.

And be aware that gravity works both ways, even for smaller objects: The Earth is pulled into a rotation by our Moon just as much as our Moon is pulled into a rotation by Earth: It isn't just the tides moved by the Moon, but the center of Earth is moving in small circles due to the moon.

So planets of equal mass would circle each other. But Jupiter is 318 x the mass of Earth, and the most massive known planet in the Universe is about 8 x the mass of Jupiter. (FWIW our Earth is 81 x our Moon).

Look up the Roche Limit; that should also tell you what your minimum orbit should be around your big planet (but actual orbit can be thousands of times bigger).

Roche Limit (rigid body) for Earth/Jupiter; 1.26 x (MassJupiter/MassEarth)^(1/3) x RadiusEarth; so it says Earth cannot be any closer than about 35,000 miles to Jupiter without breaking up. However, your planet can be quite a bit further, our Moon is about 40x its rigid body Roche Limit from Earth.

I'm not sure where you are looking, but first look here: https://www.reddit.com/r/askscience/comments/23a96x/could_an_earth_sized_object_orbit_jupiter/

The answer is Yes; any two objects can orbit each other, include Earth and Jupiter.

You need to be concerned about the Roche Limit, which tells you how far apart they must be in order to do so.

And be aware that gravity works both ways, even for smaller objects: The Earth is pulled into a rotation by our Moon just as much as our Moon is pulled into a rotation by Earth: It isn't just the tides moved by the Moon, but the center of Earth is moving in small circles due to the moon.

So planets of equal mass would circle each other. But Jupiter is 318 x the mass of Earth, and the most massive known planet in the Universe is about 30 x the mass of Jupiter. (FWIW our Earth is 81 x our Moon).

Look up the Roche Limit; that should also tell you what your minimum orbit should be around your big planet (but actual orbit can be thousands of times bigger).

Roche Limit says Earth cannot be any closer than about 67,000 miles to Jupiter without breaking up. However, your planet can be quite a bit further, our Moon is about 40x its rigid body Roche Limit from Earth. But what this means is you can put it about where you like; it does not have to be extremely far from the gas giant. If you want tidal heating of your planet (and lots of earthquakes) put it close; if your planet is warmed otherwise and you want it calmer; I'd keep it at least twenty Roche units away, say 1.4 million miles from Jupiter.

I'm not sure where you are looking, but first look here: https://www.reddit.com/r/askscience/comments/23a96x/could_an_earth_sized_object_orbit_jupiter/

The answer is Yes; any two objects can orbit each other, include Earth and Jupiter.

You need to be concerned about the Roche Limit, which tells you how far apart they must be in order to do so.

And be aware that gravity works both ways, even for smaller objects: The Earth is pulled into a rotation by our Moon just as much as our Moon is pulled into a rotation by Earth: It isn't just the tides moved by the Moon, but the center of Earth is moving in small circles due to the moon.

So planets of equal mass would circle each other. But Jupiter is 318 x the mass of Earth, and the largest known planet in the Universe is about 1.4 x the mass of Jupiter. (FWIW our Earth is 81 x our Moon).

Look up the Roche Limit; that should also tell you what your minimum orbit should be around your big planet (but actual orbit can be thousands of times bigger).

Roche Limit (rigid body) for Earth/Jupiter; 1.26 x (MassJupiter/MassEarth)^(1/3) x RadiusEarth; so it says Earth cannot be any closer than about 35,000 miles to Jupiter without breaking up. However, your planet can be quite a bit further, our Moon is about 40x its rigid body Roche Limit from Earth.

I'm not sure where you are looking, but first look here: https://www.reddit.com/r/askscience/comments/23a96x/could_an_earth_sized_object_orbit_jupiter/

The answer is Yes; any two objects can orbit each other, include Earth and Jupiter.

You need to be concerned about the Roche Limit, which tells you how far apart they must be in order to do so.

And be aware that gravity works both ways, even for smaller objects: The Earth is pulled into a rotation by our Moon just as much as our Moon is pulled into a rotation by Earth: It isn't just the tides moved by the Moon, but the center of Earth is moving in small circles due to the moon.

So planets of equal mass would circle each other. But Jupiter is 318 x the mass of Earth, and the most massive known planet in the Universe is about 8 x the mass of Jupiter. (FWIW our Earth is 81 x our Moon).

Look up the Roche Limit; that should also tell you what your minimum orbit should be around your big planet (but actual orbit can be thousands of times bigger).

Roche Limit (rigid body) for Earth/Jupiter; 1.26 x (MassJupiter/MassEarth)^(1/3) x RadiusEarth; so it says Earth cannot be any closer than about 35,000 miles to Jupiter without breaking up. However, your planet can be quite a bit further, our Moon is about 40x its rigid body Roche Limit from Earth.

I'm not sure where you are looking, but first look here: https://www.reddit.com/r/askscience/comments/23a96x/could_an_earth_sized_object_orbit_jupiter/

The answer is Yes; any two objects can orbit each other, include Earth and Jupiter.

You need to be concerned about the Roche Limit, which tells you how far apart they must be in order to do so.

And be aware that gravity works both ways, even for smaller objects: The Earth is pulled into a rotation by our Moon just as much as our Moon is pulled into a rotation by Earth: It isn't just the tides moved by the Moon, but the center of Earth is moving in small circles due to the moon.

(corrected thanks to sphenning, my mistake).

So planets of equal mass would circle each other. But Jupiter is 318 x the mass of Earth, and the largest known planet in the Universe is about 1.4 x the mass of Jupiter. (FWIW our Earth is 81 x our Moon).

Look up the Roche Limit; that should also tell you what your minimum orbit should be around your big planet (but actual orbit can be thousands of times bigger).

Roche Limit (rigid body) for Earth/Jupiter; 1.26 x (MassJupiter/MassEarth)^(1/3) x RadiusEarth; so it says Earth cannot be any closer than about 35,000 miles to Jupiter without breaking up. However, your planet can be quite a bit further, our Moon is about 40x its rigid body Roche Limit from Earth.

I'm not sure where you are looking, but first look here: https://www.reddit.com/r/askscience/comments/23a96x/could_an_earth_sized_object_orbit_jupiter/

The answer is Yes; any two objects can orbit each other, include Earth and Jupiter.

You need to be concerned about the Roche Limit, which tells you how far apart they must be in order to do so.

And be aware that gravity works both ways, even for smaller objects: The Earth is pulled into a rotation by our Moon just as much as our Moon is pulled into a rotation by Earth: It isn't just the tides moved by the Moon, but the center of Earth is moving in small circles due to the moon.

So planets of equal mass would circle each other. But Jupiter is 318 x the mass of Earth, and the largest known planet in the Universe is about 1.4 x the mass of Jupiter. (FWIW our Earth is 81 x our Moon).

Look up the Roche Limit; that should also tell you what your minimum orbit should be around your big planet (but actual orbit can be thousands of times bigger).

Roche Limit (rigid body) for Earth/Jupiter; 1.26 x (MassJupiter/MassEarth)^(1/3) x RadiusEarth; so it says Earth cannot be any closer than about 35,000 miles to Jupiter without breaking up. However, your planet can be quite a bit further, our Moon is about 40x its rigid body Roche Limit from Earth.